Timber
- Created by: Evie_Rouxel
- Created on: 08-11-19 09:59
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- Timber
- Conversion
- After a tree is felled and cut into manageable lengths, it is then converted into planks at which point it is known as timber.
- Timber is supplied in two main types of finish: rough sawn or planed all round.(PAR)
- Rough sawn timber has not been planed and is rough to the touch. it is mostly used for exterior use where the finish isn't important.
- Planed all round (PAR) has a much smoother finish as it have been mechanically planed on all sides.It is used for furniture and internal features such as windows and doors. It is less absorbent than rough timber.
- Seasoning
- Once timebr is converted into a workable form, it is seasoned in order to reduce the moisture content.
- Newly felled trees will have a moisture content of over 50% and is known as green timber. The moisture content needs to be reduced below 20% for most exterior applications and below 15% for interior work and below 10% for interior areas that are heated constantly.
- Uneven evaporation ofhte water content can cause some common faults to occur such as twisting, cupping and bowing which can make the timber useless for lots of tasls.
- There are two methods of seasoning:air drying or kiln drying.
- Air dried timber is stacked so air can circulate around the planks and evaporation can take place.
- Kiln dried timber can have a much lower moisture content and is a much faster process. it costs more than air drying as heat and pressure is It is much less prone to flaunts.
- Manufactured board
- Natural timber is combined with adhesive to make manufactured boards.
- Each manufactured board is manufactured in a slightly different way; the two main processes are lamination and compression.
- Lamination is used on plywood and block wood where layers of wood are bonded together using an adhesive.
- Compression is used on medium density fibre board, chipboard, oriented strand board (OSB) and hardboard.
- Each manufactured board is manufactured in a slightly different way; the two main processes are lamination and compression.
- Natural timber is combined with adhesive to make manufactured boards.
- Conversion
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